Can't solve a few errors. . .

[imajar]

Hi everyone, 

I've attached an assembly with two problems I cannot figure out and would appreciate some help.

I'm running Inventor 2021.2.2 and Inventor Nastran 2021.2.0.493

1.  When I click run I get the error "Could not find a valid FE Mesh, Please Update FE mesh and Try again!" repeated 4 times, and then it runs normally.  I cannot seem to get a good answer from the forums on how to solve this, the one answer I could find is to suppress components one by one which is a ridiculous solution procedure.

2.  The solution fails due to a problem with Contacts 18 and 19.  If I suppress those, it solves - but I cannot figure out what the issue is with those contacts.

Any help is appreciated.

As a side note, with assemblies like this with frames it is mega annoying that every time I tweak the frame, Inventor nastran re-assigns all the members that changed from solid to beam - and then I have to change it back, research contacts, etc.  Could someone get that on a just do it list please?  (sometimes it is nice to have the functionality, but rather than wrapping it up in environment initialization, instead add a manually activated function?)

[Roelof.Feijen]

Hi @imajar ,

I am unable to solve your problem, but I want to respond to your "side note".

Have you ever thought about a different approach when you want to use Frame Generator and not use Line elements in Nastran? You could build a Derive Part with Multi Bodies and than recreate your assembly using the Make Components workflow. In that case you still can use Frame Generator and keep your analysis geometry up-to-date. See the video below.

[imajar]

Hi @Roelof.Feijen,

I very much appreciate the time you took to demonstrate the workflow!  That does look like a good way to analyze frame models.

Meanwhile if anyone knows how to resolve the original issues I mentioned it would be appreciated just so that I can troubleshoot things better in the future.

[martin_madaj]

Hi @imajar,

I did not check your model but regarding your item #1, I consider this to be a really annoying error that is sometimes very difficult to debug. A few days back I found it may be caused by too coarse mesh in some locations of the model. Imagine that a load/constraint is applied to some edge but the mesh is shifted sideways because it's not refined enough.
Another reason may be that you mixed your simulation geometry and some construction/auxiliary geometry (i.e. two lines or points at the same location with the load/constraint applied to an incorrect entity).

Regards,
Martin M.